1. The Field of the Invention
The present invention relates to drilling systems and to isolation systems for isolating forces generated by a drill head in particular.
2. The Relevant Technology
Core drilling allows samples of subterranean materials from various depths to be obtained for many purposes. For example, drilling a core sample and testing the retrieved core helps determine what materials are present or are likely to be present in a given formation. For instance, a retrieved core sample can indicate the presence of petroleum, precious metals, and other desirable materials. In some cases, core samples can be used to determine the geological timeline of materials and events. Accordingly, core samples can be used to determine the desirability of further exploration in a given area.
Although there are several ways to collect core samples, core barrel systems are often used for core sample retrieval. Core barrel systems include an outer tube with a coring drill bit secured to one end. The opposite end of the outer tube is often attached to a drill string that extends vertically to a drill head that is often located above the surface of the earth. The core barrel systems also often include an inner tube located within the outer tube. As the drill bit cuts formations in the earth, the inner tube can be filled with a core sample. Once a desired amount of a core sample has been cut, the inner tube and core sample can be brought up through the drill string and retrieved at the surface.
Sonic head assemblies are often used to vibrate a drill string and the attached coring barrel and drill bit at high frequency to allow the drill bit and core barrel to slice through the formation as the drill bit rotates. The vibrations transmitted to the drill string can be extremely large, high-frequency forces. While such forces can allow the drill bit to slice through formations, if such forces are transmitted to other parts of the drilling systems, the magnitude and frequency of these forces can result in undesirable shaking and/or damage to the drilling systems.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced